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Altera_Forum's avatar
Altera_Forum
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15 years ago

problem with value 'X' in VHDL

Dear my best friends I used vhdl to calculate SVPWM algorithm. I used LPM library for divider. I'd already initial value for all of signal, but It still has "X" value. This is LPM library m0...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

The synthesisor will place add/dub/multiply for you, from the LPM library if you write things like

c <= a + b;

c <= a * b;

etc.

And it will probably do a better job at minimising the logic.

The only area where you really have to be careful is dividers because you cannot control the internal pipelining very easily without using the lpm_divide megafunction.